KR102035987B1 - Salt and photoresist composition comprising the same - Google Patents

Abstract

상기 화학식 I에서,
Q¹ 및 Q²는 각각 독립적으로 불소 원자 또는 C1-C6 퍼플루오로알킬 그룹이고,
L¹은 C1-C17 2가 포화 탄화수소 그룹이고, 여기서, 하나 이상의 -CH₂-는 -O- 또는 -CO-에 의해 대체될 수 있고,
L²는 단일 결합 또는 C1-C6 알칸디일 그룹이고, 여기서, 하나 이상의 -CH₂-는 -O- 또는 -CO-에 의해 대체될 수 있고,
Y는 하나 이상의 치환체를 가질 수 있는 C3-C18 지환족 탄화수소 그룹이고, 상기 지환족 탄화수소 그룹 중의 하나 이상의 -CH₂-는 -O-, -CO- 또는 -SO₂-에 의해 대체될 수 있고,
Z⁺는 유기 카운터 이온이다.The present invention provides salts represented by Formula I:
Formula I

In Formula I,
Q ¹ and Q ² are each independently a fluorine atom or a C1-C6 perfluoroalkyl group,
L ¹ is a C1-C17 divalent saturated hydrocarbon group, wherein one or more -CH ₂ -can be replaced by -O- or -CO-,
L ² is a single bond or a C1-C6 alkanediyl group, wherein one or more -CH ₂ -can be replaced by -O- or -CO-,
Y is a C3-C18 cycloaliphatic hydrocarbon group which may have one or more substituents, and one or more -CH ₂ -in the cycloaliphatic hydrocarbon group can be replaced by -O-, -CO- or -SO _2- ,
Z ⁺ is an organic counter ion.

Description

Salt and photoresist composition comprising the same {Salt and photoresist composition comprising the same}

The present invention relates to salts and photoresist compositions comprising them.

Photoresist compositions are used for semiconductor microfabrication using lithography processes.

US 2007/0122750 A1 describes photoresist compositions comprising as an acid generator a salt represented by the formula:

Summary of the Invention

The present invention is to provide a salt suitable for an acid generator and a photoresist composition comprising the same.

The present invention relates to:

<1> Salts represented by Formula I:

Formula I

In Formula I,

Q ¹ and Q ² are each independently a fluorine atom or a C1-C6 perfluoroalkyl group,

L ¹ is a C1-C17 divalent saturated hydrocarbon group, wherein one or more -CH ₂ -can be replaced by -O- or -CO-,

L ² is a single bond or a C1-C6 alkanediyl group, wherein one or more -CH ₂ -can be replaced by -O- or -CO-,

Y is a C3-C18 cycloaliphatic hydrocarbon group which may have one or more substituents, and one or more -CH ₂ -in the cycloaliphatic hydrocarbon group can be replaced by -O-, -CO- or -SO _2- ,

Z ⁺ is an organic counter ion.

<2> The compound of <1>, wherein L ¹ is a C1-C6 alkanediyl group or * -CO-OL ^b2 -** [where L ^b2 is a C1-C15 divalent saturated hydrocarbon group and * is -C ( Q ¹ ) (Q ² ) — indicates the binding position to **, ** indicates the binding position to —O—CO—OL ² —Y].

<3> The compound of <1>, wherein L ¹ is a methylene group, * -CO-O-CH ₂ -CH ₂ -** [where * represents a binding position to -C (Q ¹ ) (Q ² )- And ** indicates a bonding position to —O—CO—OL ² —Y] or a group represented by the following formula:

In the above formula, * indicates a binding position to —C (Q ¹ ) (Q ² ) —, and ** indicates a binding position to —O—CO—OL ² —Y.

<4> The salt according to any one of <1> to <3>, wherein L ² is a single bond or a methylene group.

<5> The salt according to any one of <1> to <4>, wherein Z ⁺ is an arylsulfonium cation.

<6> Acid generator containing the salt in any one of <1>-<5>.

<7> A photoresist composition comprising an acid generator according to <6>, and a resin having an acid-labile group, which is insoluble or poorly soluble in an aqueous alkali solution but soluble in an aqueous alkali solution by the action of an acid.

<8> The photoresist composition of <7> which further contains a basic compound.

<9> A method for producing a photoresist pattern, comprising the following steps (1) to (5):

(1) applying the photoresist composition according to <7> or <8> on a substrate,

(2) drying to form a photoresist film,

(3) exposing the photoresist film to radiation,

(4) baking the exposed photoresist film, and

(5) developing the baked photoresist film with an alkaline developer to form a photoresist pattern.

Description of the Preferred Aspects

Salts of the present invention are represented by formula (hereinafter abbreviated as salt (I)):

Formula I

In Formula I,

Q ¹ and Q ² are each independently a fluorine atom or a C1-C6 perfluoroalkyl group,

L ¹ is a C1-C17 divalent saturated hydrocarbon group, wherein one or more -CH ₂ -can be replaced by -O- or -CO-,

L ² is a single bond or a C1-C6 alkanediyl group, wherein one or more -CH ₂ -can be replaced by -O- or -CO-,

Y is a C3-C18 cycloaliphatic hydrocarbon group which may have one or more substituents, and one or more -CH ₂ -in the cycloaliphatic hydrocarbon group can be replaced by -O-, -CO- or -SO _2- ,

Z ⁺ is an organic counter ion.

Examples of the C1-C6 perfluoroalkyl group include trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, perfluorosecondary- Butyl groups, perfluoro-tert-butyl groups, perfluoropentyl groups and perfluorohexyl groups are included, with trifluoromethyl groups being preferred. Preferably, Q ¹ and Q ² are each independently a fluorine atom or a trifluoromethyl group, and more preferably, Q ¹ and Q ² are fluorine atoms.

Examples of the C1-C17 divalent saturated hydrocarbon group include methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, butane-1,3 -Diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonan-1,9-diyl group, decane -1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane C1-C17 linear alkanediyl groups such as the -1,15-diyl group, the hexadecane-1,16-diyl group and the heptadecan-1,17-diyl group; Ethane-1,1-diyl group, propane-1,1-diyl group, propane-2,2-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2- C2-C17 branched alkanediyl groups such as methylpropane-1,2-diyl group, pentane-1,4-diyl group and 2-methylbutane-1,4-diyl group; Cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,2-diyl group, 1-methylcyclohexane-1,2-diyl group, cyclohexane-1,4- Divalent monocyclic saturated aliphatic hydrocarbon groups such as cycloalkanediyl groups such as diyl groups, cyclooctane-1,2-diyl groups and cyclooctane-1,5-diyl groups; Norbornane-2,3-diyl group, norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,2-diyl group, adamantane-1, Divalent polycyclic saturated aliphatic hydrocarbon groups such as 5-diyl group and adamantane-2,6-diyl group; And a group formed by combining two or more groups selected from the group consisting of the aforementioned groups.

One or more -CH ₂ - an example of a C1-C17 saturated hydrocarbon group of 2 is replaced by -O- or -CO- is ^{* -CO-OL 1b1 - **,} * -CO-OL 1b3 -CO-OL 1b2 ^{- **, * -CO-OL 1b5} -OL 1b4 - ** and * -L ^1b7 -OL ^1b6 - ** are included, wherein, L ^1b1 is a C1-C15 saturated hydrocarbon group is 2, L is ^1b2 C1 -C12 divalent saturated hydrocarbon group, L ^1b3 is a C1-C12 divalent saturated hydrocarbon group, provided that the total carbon number of L ^1b2 and L ^1b3 is 1 to 13, and L ^1b4 is a C1-C13 divalent saturated hydrocarbon group , L ^1b5 is a C1-C13 divalent saturated hydrocarbon group, provided that the total carbon number of L ^1b4 and L ^1b5 is 1 to 14, L ^1b6 is a C1-C15 divalent saturated hydrocarbon group, L ^1b7 is C1-C15 2 Is a saturated hydrocarbon group, provided that L ^1b6 and L ^1b7 have from 1 to 16 carbon atoms, and * represents a bonding position to —C (Q ¹ ) (Q ² ) — and ** represents —O—CO— The binding position for OL ² -Y is shown.

Examples of * -CO-OL ^1b1 -** include:

Examples of * -CO-OL ^1b3 -CO-OL ^1b2 -** include:

Examples of * -CO-OL ^1b5 -OL ^1b4 -** include:

Examples of * -L ^1b7 -OL ^1b6 -** include:

L ¹ is preferably a C1-C6 alkanediyl group or * -CO-OL ^b2 -**, more preferably a methylene group, * -CO-O-CH ₂ -CH ₂ -** or in the formula The group shown is:

Examples of C1-C6 alkanediyl groups represented by L ² include methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group and hexane- C1-C6 linear alkanediyl groups such as 1,6-diyl groups, propane-1,2-diyl groups, butane-1,3-diyl groups, 2-methylpropane-1,3-diyl groups, 2- C2-C6 branched alkanediyl groups such as methylpropane-1,2-diyl group, 1-methylbutane-1,4-diyl group and 2-methylbutane-1,4-diyl group.

L ² is preferably a single bond or a methylene group.

The C3-C18 monovalent alicyclic hydrocarbon group represented by Y may be monocyclic or polycyclic.

Examples of the monocyclic monovalent alicyclic hydrocarbon group include cyclopropyl group, cyclobutyl group, ethylcyclobutyl group, cyclopentyl group, cyclohexyl group, methylcyclohexyl group, dimethylcyclohexyl group, cycloheptyl group and cyclooctyl C3-C18 cycloalkyl groups such as groups are included. Examples of the polycyclic monovalent alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group, methylnorbornyl group, and groups represented by the following formulae.

The C3-C18 alicyclic hydrocarbon group may have one or more substituents, and examples of the substituent include a halogen atom, a hydroxyl group, a C1-C12 alkoxy group, a C6-C18 aromatic hydrocarbon group, a C7-C21 aralkyl group, C2 -C4 acyl group, glycidyloxy group and-(CH ₂ ) _j2 -O-CO-R ^i1- , wherein R ⁱ¹ is a C1-C16 aliphatic hydrocarbon group, a C3-C16 saturated alicyclic hydrocarbon group or C6-C18 Aromatic hydrocarbon group, j2 is an integer of 0 to 4), and the aromatic hydrocarbon group and the C7-C21 aralkyl group are one selected from the group consisting of C1-C8 alkyl group, halogen atom and hydroxyl group It may have more than one substituent.

Examples of the halogen atom include fluorine atom, chlorine atom, bromine atom and iodine atom. Examples of such acyl groups include acetyl groups, propionyl groups and butyryl groups. Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group and dodecyloxy group do. Examples of the aromatic hydrocarbon group include phenyl group, naphthyl group, anthryl group, p-methylphenyl group, p-tert-butylphenyl group, p-adamantylphenyl group, tolyl group, xylyl group, cumyl group, C6-C18 aryl groups such as mesityl group, biphenyl group, phenanthryl group, 2,6-diethylphenyl group and 2-methyl-6-ethylphenyl group. Examples of the aralkyl group include benzyl group, phenethyl group, phenylpropyl group, trityl group, naphthylmethyl group and naphthylethyl group. Examples of such aliphatic hydrocarbon groups include C1-C16 alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group and octyl group.

One or more -CH ₂ -in the monovalent alicyclic hydrocarbon group may be replaced by -O-, -CO- or -SO _2- , and one or more -CH ₂ -is -O-, -CO- or- Examples of monovalent alicyclic substituted by SO ₂ -include a group having a cyclic ether structure, a group having a cyclic ketone structure, a group having a sultone ring structure and a group having a lactone ring structure.

Preferred examples of Y include groups represented by the formulas Y1 to Y29, where * represents a binding position to L ² .

Of these, groups represented by the formulas Y1 to Y19 and Y27 to Y29 are preferable, groups represented by the formulas Y11, Y14, Y15, Y19, Y27, Y28, and Y29 are more preferable, and groups represented by the formulas Y11 and Y14 Are particularly preferred.

Examples of Y having one or more substituents include the following.

Y is preferably a C3-C12 cycloalkyl group, which may have one or more substituents, wherein one or more -CH ₂ -may be replaced by -O-, -CO- or -SO _2- , or It is an adamantyl group, More preferably, it is an adamantyl group, an oxoadamantyl group, or a hydroxyadamantyl group.

Preferred examples of the anion moiety of the salt (I) include anions represented by the following formulas 1a-1 to 1a-20.

Examples of organic cations represented by Z ⁺ include organic onium cations such as organic sulfonium cations, organic iodonium cations, organic ammonium cations, organic benzothiazolium cations and organic phosphonium cations. Of these, organic sulfonium cations and organic iodonium cations are preferred, and arylsulfonium cations are more preferred. As used herein, "arylsulfonium cation" means an organic sulfonium cation having at least one aryl group.

Preferred examples of the organic counter ion of the salt (I) include organic cations represented by the following formulas b2-1 to b2-4.

In Chemical Formulas b2-1 to b2-4,

R ^b4 , R ^b5 and R ^b6 are independently a C1-C30 alkyl group, a halogen atom, which may have one or more substituents selected from the group consisting of a hydroxyl group, a C1-C12 alkoxy group and a C6-C18 aromatic hydrocarbon group C3-C18 alicyclic hydrocarbon group which may have one or more substituents selected from the group consisting of C2-C4 acyl group and glycidyloxy group, or halogen atom, hydroxyl group, C1-C18 aliphatic hydrocarbon group, C3- A C6-C18 aromatic hydrocarbon group which may have one or more substituents selected from the group consisting of a C18 alicyclic hydrocarbon group and a C1-C12 alkoxy group, R ^b4 and R ^b5 , R ^b4 and R ^b6 , or R ^b5 and R ^b6 May combine with each other to form a ring containing S ⁺ ,

R ^b7 and R ^b8 , at each occurrence, are independently a hydroxyl group, a C1-C12 alkyl group or a C1-C12 alkoxy group,

m2 and n2 are independently an integer of 0 to 5,

R ^b9 and R ^b10 are independently a C1-C18 alkyl group or a C3-C18 saturated cyclic hydrocarbon group, or R ^b9 and R ^b10 combine to form a ring together with adjacent S ⁺ to form a C2-C11 divalent acyclic ) Form a hydrocarbon group, and at least one of the divalent acyclic hydrocarbon groups -CH ₂ -can be replaced by -CO-, -O- or -S-,

R ^b11 is a hydrogen atom, a C1-C18 alkyl group, a C3-C18 alicyclic hydrocarbon group or a C6-C18 aromatic hydrocarbon group, and R ^b12 is a C1-C12 alkyl group, a C3-C18 alicyclic hydrocarbon group or a C6-C18 aromatic hydrocarbon Group, wherein the aromatic hydrocarbon group may have one or more substituents selected from the group consisting of a C1-C12 alkyl group, a C1-C12 alkoxy group, a C3-C18 alicyclic hydrocarbon group and a C2-C13 acyloxy group R ^b11 and R ^b12 combine with each other to form a C 1 -C 10 divalent acyclic hydrocarbon group which forms together with an adjacent —CHCO— a 2-oxocycloalkyl group, wherein at least one of the divalent acyclic hydrocarbon groups is -CH ₂ -may be replaced by -CO-, -O- or -S-,

R ^b13 , R ^b14 , R ^b15 , R ^b16 , R ^b17 and R ^b18 are independently a hydroxyl group, a C1-C12 alkyl group or a C1-C12 alkoxy group,

L ^b11 is -S- or -O-,

o2, p2, s2 and t2 are each independently an integer of 0 to 5,

q2 and r2 are each independently an integer of 0 to 4,

u2 is 0 or 1.

The alkyl group represented by R ^b9 to R ^b11 preferably has 1 to 12 carbon atoms. The alicyclic hydrocarbon group represented by R ^b9 to R ^b11 preferably has 3 to 18 carbon atoms, more preferably 4 to 12 carbon atoms.

Preferred examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, secondary-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group and 2-ethylhexyl group Included. Preferred examples of the cycloaliphatic hydrocarbon group include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclodecyl group, 2-alkyladamantan-2-yl group, 1- (adama Tan-1-yl) alkan-1-yl groups and isobornyl groups. Preferred examples of the aromatic group include phenyl group, 4-methylphenyl group, 4-ethylphenyl group, 4-tert-butylphenyl group, 4-cyclohexylphenyl group, 4-methoxyphenyl group, biphenyl group and naphthyl Groups are included. Examples of such alkyl groups having aromatic hydrocarbon groups include aralkyl groups such as benzyl groups. Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, secondary-butoxy group, tert-butoxy group, pentyloxy group, hexyloxy group, Heptyloxy groups, octyloxy groups, 2-ethylhexyloxy groups, nonyloxy groups, decyloxy groups, undecyloxy groups and dodecyloxy groups.

Examples of the C3-C12 divalent acyclic hydrocarbon group formed by bonding of R ^b9 and R ^b10 include trimethylene group, tetramethylene group and pentamethylene group. Examples of ring groups formed by adjacent S ⁺ and divalent acyclic hydrocarbon groups include, but are not limited to, thiol-1- 'rings (tetrahydrothiphenium rings), thian-1-' rings and 1,4-oxatian-4- ' Rings are included. Preferred are C3-C7 divalent acyclic hydrocarbon groups.

Examples of the C1-C10 divalent acyclic hydrocarbon group formed by bonding of R ^b11 and R ^b12 include a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, and a pentamethylene group. Of things are included.

Preferred are C1-C5 divalent acyclic hydrocarbon groups.

Examples of the C2-C13 acyloxy group include acetyloxy group, propionyloxy group, butyryloxy group, isopropylcarbonyloxy group, butylcarbonyloxy group, secondary-butylcarbonyloxy group, tert-butyl Carbonyloxy groups, pentylcarbonyloxy groups, hexylcarbonyloxy groups, octylcarbonyloxy groups and 2-ethylhexylcarbonyloxy groups.

Examples of the organic cations represented by the formulas b2-1 to b2-4 include those described in JP 2010-204646 A.

Of these, cations of the formula (b2-1) are preferred, and cations of the formula (b2-1-1) are more preferred. Particular preference is given to triphenylsulfonium cations and tritolylsulfonium cations.

In Chemical Formula b2-1-1,

R ^b19 , R ^b20 and R ^b21 are independently at each occurrence a halogen atom (preferably a fluorine atom), a hydroxyl group, a C1-C12 alkyl group, a C3-C18 alicyclic hydrocarbon group or a C1-C12 alkoxy group Wherein the alkyl group, the alicyclic hydrocarbon group and the alkoxy group are a group consisting of a halogen atom, a hydroxyl group, a C1-C12 alkoxy group, a C6-C18 aromatic hydrocarbon group, a C2-C4 acyl group or a glycidyloxy group May have one or more substituents selected from R ^b19 and R ^b20 , R ^b19 and R ^b21 , or R ^b20 and R ^b21 combine with each other to form a single bond, -O- or C1-C4 aliphatic divalent hydrocarbon group Thereby forming a sulfur-containing ring together with S ⁺ ,

v2, w2 and x2 are each independently an integer of 0-5.

Preferably, R ^b19 , R ^b20 and R ^b21 are independently at each occurrence a halogen atom, a hydroxyl group, a C1-C12 alkyl group or a C1-C12 alkoxy group and v2, w2 and x2 are each independently It is an integer of 0-5. More preferably, R ^b19 , R ^b20 and R ^b21 are independently at each occurrence a fluorine atom, a hydroxyl group, a C1-C12 alkyl group or a C1-C12 alkoxy group and v2, w2 and x2 are each independently 0 or 1.

Examples of the organic counter ion include the followings.

Examples of salt (I) include salts where the anion is any of the anions described above and the cation is any of the organic counter ions. Preferred examples of salt (I) include the salts described in Tables 1-5.

Of these, the following salts are preferred.

Salt (I) can be prepared by reacting a salt of formula (I-c) with a compound of formula (I-d) in the presence of a catalyst such as potassium carbonate in a solvent such as N, N-dimethylformamide.

Wherein Q ¹ , Q ² , L ¹ , L ² , Y and Z ⁺ are as defined above.

Examples of the compound of Formula I-d include 3- (hydroxymethyl) adamantan-1-ol.

The salt of formula (I-c) may be prepared by reacting a salt of formula (I-a) with a compound of formula (I-b) in a solvent such as acetonitrile.

Wherein Q ¹ , Q ² , L ¹ and Z ⁺ are as defined above.

The salt of formula (I-a) may be prepared according to the method described in JP 2006-257078 A.

Acid generators of the present invention include salt (I). The acid generator of the present invention may contain two or more salts (I). In addition to salt (I), the acid generator of the present invention may contain one or more known acid generators other than salt (I). Examples of one or more known acid generators other than salt (I) include salts consisting of the aforementioned organic counter ions of salt (I) and known anions other than the aforementioned anions of salt (I), and salts (I) Salts consisting of known organic counter ions other than the anions mentioned above and cations of salts (I).

Specific examples of known acid generators other than the salt (I) include salts represented by the following formulas B1-1 to B1-17, and salts containing triphenylsulfonium cation or tritolylsulfonium cation More preferably, salts represented by the formulas B1-1, B1-2, B1-3, B1-6, B1-7, B1-11, B1-12, B1-13 and B1-14 are particularly preferred.

The acid generator of the present invention may consist of salt (I).

When the acid generator of the present invention contains salt (I) and acid generators other than salt (I), the content of salt (I) is preferably 10 parts by weight or more per 100 parts by weight of the acid generator of the present invention, More preferably 30 parts by weight or more, and the content of salt (I) is preferably 90 parts by weight or less, more preferably 70 parts by weight or less per 100 parts by weight of the acid generator of the present invention.

When the acid generator of the present invention contains salt (I) and acid generators other than salt (I), the ratio of salt (I) to acid generators other than salt (I) (salt (I) / salt ( Acid generators other than I) are preferably 90/10 to 10/90, more preferably 85/15 to 15/85.

Next, the photoresist composition of the present invention will be described.

The photoresist composition of the present invention comprises the acid generator of the present invention and a resin having an acid-labile group, which is insoluble or poorly soluble in the aqueous alkali solution but soluble in the aqueous alkali solution by the action of an acid.

The resin is insoluble or poorly soluble in aqueous alkali solution but soluble in aqueous alkali solution by the action of acid. The resin has one or more acid-labile groups. As used herein, "acid-labile group" means a group that can be removed by the action of an acid.

Examples of acid-labile groups include groups represented by the formula (1).

Formula 1

In Chemical Formula 1,

R ^a1 , R ^a2 and R ^a3 are each independently a C1-C8 alkyl group or a C3-C20 alicyclic hydrocarbon group, R ^a1 and R ^a2 are bonded to each other, and C 3 together with the carbon atom to which R ^a1 and R ^a2 are bonded -C20 ring can be formed, and the aliphatic hydrocarbon group, the alicyclic hydrocarbon group and one or more -CH ₂ -of the ring can be replaced by -O-, -S- or -CO-.

Examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, pentyl group, hexyl group, heptyl group and octyl group. The cycloaliphatic hydrocarbon group may be monocyclic or polycyclic. Examples of such alicyclic hydrocarbon groups include monocyclic alicyclic groups such as C3-C20 cycloalkyl groups (e.g., cyclopentyl groups, cyclohexyl groups, methylcyclohexyl groups, dimethylcyclohexyl groups, cycloheptyl groups, and cyclooctyl groups). Hydrocarbon groups and polycyclic alicyclic hydrocarbon groups such as decahydronaphthyl group, adamantyl group, norbornyl group, methylnorbornyl group and the following groups are included:

The alicyclic hydrocarbon group preferably has 3 to 16 carbon atoms.

Examples of the ring formed by bonding of R ^a1 and R ^a2 to each other include the following groups, wherein R ^a3 is as defined above, and the ring preferably has 3 to 12 carbon atoms.

A group of formula (1), eg, tert-butyl group, wherein R ^a1 , R ^a2 and R ^a3 are each independently a C1-C8 alkyl group; A group of formula 1 wherein R ^a1 and R ^a2 combine with each other to form an adamantyl ring and R ^a3 is a C1-C8 alkyl group, for example, a 2-alkyladamantan-2-yl group; And a group of formula 1 wherein R ^a1 and R ^a2 are C1-C8 alkyl groups and R ^a3 is an adamantyl group, for example, a 1- (adamantane-1-yl) -1-alkylalkoxycarbonyl group desirable.

Examples of acid-labile groups include groups represented by the formula (20).

Formula 20

In Chemical Formula 20,

R ^b1 and R ^b2 are each independently a hydrogen atom or a C1-C12 hydrocarbon group,

R ^b3 is a C1-C20 hydrocarbon group,

R ^b2 and R ^b3 may be bonded to each other to form a C3-C20 ring together with the carbon atom and oxygen atom to which they are bonded, wherein at least one of the hydrocarbon group and the ring -CH ₂ -is -O-, -S Or by -CO-.

The group represented by the formula (20) has an acetal or ketal structure.

Examples of such hydrocarbon groups include aliphatic hydrocarbon groups, cycloaliphatic hydrocarbon groups, and aromatic hydrocarbon groups. Examples of the aliphatic hydrocarbon group and the alicyclic hydrocarbon group include the same as described above. Examples of the aromatic hydrocarbon group include phenyl group, naphthyl group, p-methylphenyl group, p-tert-butylphenyl group, p-adamantylphenyl group, tolyl group, xylyl group, cumyl group, mesityl group, Aryl groups such as biphenyl group, anthryl group, phenanthryl group, 2,6-diethylphenyl group and 2-methyl-6-ethylphenyl group.

It is preferable that at least one of R ^b1 and R ^b2 is a hydrogen atom.

Examples of the group represented by the formula (20) include the following ones.

The resin has one or more structural units derived from monomers having acid-labile groups in the side chain.

The monomer having an acid-labile group is preferably a monomer having an acid-labile group in the side chain and having a carbon-carbon double bond, more preferably an acrylate monomer having an acid-labile group in the side chain, or an acid-labile group It is a methacrylate monomer which has in a side chain.

A monomer having a group represented by the formula (10) or (20) in the side chain and having a carbon-carbon double bond is preferable, and an acrylate monomer having the group represented by the formula (10) in the side chain, or a meta having a group represented by the formula (10) in the side chain. More preferred are acrylate monomers.

R ^a1 and R ^a2 are combined, they are combined together with the carbon atom acrylate monomer having a group of formula 10 to form a C5-C20 cycloaliphatic ring (alicycle) in the side chain, or R ^a1 and R ^a2 are combined with each other Particular preference is given to methacrylate monomers having in the side chain a group of the formula (10) which together with the carbon atoms to which they are attached form a C5-C20 alicyclic ring.

Preferred examples of structural units derived from monomers having acid-labile groups in the side chain include structural units represented by the formulas a1-1 and a1-2:

In Chemical Formulas a1-1 and a1-2,

R ^a4 and R ^a5 are each independently a hydrogen atom or a methyl group,

R ^a6 and R ^a7 are each independently a C1-C8 alkyl group or a C3-C10 alicyclic hydrocarbon group,

L ^a1 and L ^a2 are each independently * -O- or * -O- (CH ₂ ) _k1 -CO-O-, where * represents a bonding position to -CO-, and k1 is an integer from 1 to 7 )

m1 is an integer of 0 to 14,

n1 is an integer of 0 to 10,

n1 'is an integer of 0-3.

The alkyl group preferably has 1 to 6 carbon atoms and the alicyclic hydrocarbon group preferably has 3 to 8 carbon atoms, more preferably 3 to 6 carbon atoms. The alicyclic hydrocarbon group is preferably a saturated aliphatic cyclic hydrocarbon group.

Examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, tert-butyl group, 2,2-dimethylethyl group, 1-methylpropyl group, 2,2-dimethylpropyl group, 1-ethylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-propylbutyl group, pentyl group, 1-methylpentyl group, hexyl group, 1,4-dimethylhexyl group, Heptyl groups, 1-methylheptyl groups and octyl groups. Examples of the alicyclic hydrocarbon group include monocyclic cycloaliphatic hydrocarbon groups such as cyclohexyl group, methylcyclohexyl group, dimethylcyclohexyl group, cycloheptyl group and methylcycloheptyl group, and decahydronaphthyl group, adamantyl Polycyclic alicyclic hydrocarbon groups such as groups, norbornyl groups, methylnorbornyl groups and the following groups are included.

L ^a1 is preferably * -O- or * -O- (CH ₂ ) _f1 -CO-O-, where * represents a bonding position to -CO- and f1 is an integer from 1 to 4, More preferably * -O- or * -O-CH ₂ -CO-O-, particularly preferably * -O-. L ^a2 is preferably * -O- or * -O- (CH ₂ ) _f1 -CO-O-, where * represents a bonding position to -CO-, f1 is as defined above, and more. It is preferably * -O- or * -O-CH ₂ -CO-O-, particularly preferably * -O-.

In the above formula a1-1, m1 is preferably an integer of 0 to 3, more preferably 0 or 1. In the formula a1-2, n1 is preferably an integer of 0 to 3, more preferably 0 or 1, and n1 'is preferably 0 or 1.

R ^a4 and R ^a5 are preferably methyl groups.

Examples of the monomer having a structural unit represented by Chemical Formula a1-1 include monomers described in JP 2010-204646 A, and monomers represented by the following Chemical Formulas a1-1-1 to a1-1-8 are preferable. More preferred are monomers represented by the following formulas a1-1-1 to a1-1-4.

Examples of the monomer having a structural unit represented by Chemical Formula a1-2 include 1-ethylcyclopentan-1-yl acrylate, 1-ethylcyclopentan-1-yl methacrylate, and 1-ethylcyclohexane-1-yl Acrylate, 1-ethylcyclohexane-1-yl methacrylate, 1-ethylcycloheptan-1-yl acrylate, 1-ethylcycloheptan-1-yl methacrylate, 1-methylcyclopentan-1-yl Acrylate, 1-methylcyclopentan-1-yl methacrylate, 1-isopropylcyclopentan-1-yl acrylate and 1-isopropylcyclopentan-1-yl methacrylate; Monomers represented by 2-1 to a1-2-6 are preferable, monomers represented by the following formulas a1-2-3 to a1-2-4 are more preferable, and monomers represented by the following formula a1-2-3 Is particularly preferred.

The content in the resin of the structural unit derived from the monomer having an acid-labile group is generally 10 to 95 mol%, preferably 15 to 90 mol%, more preferably based on 100 mol% of all the structural units of the resin. Preferably from 20 to 85 mole%. Based on the total amount of monomers used to prepare the resin, by adjusting the amount of monomer having an acid-labile group, the content in the resin of the structural unit derived from the monomer having the acid-labile group can be controlled.

When the resin contains the structural unit represented by the formula a1-1 or a1-2, the content in the resin of the structural unit represented by the formula a1-1 or a1-2 is 100 mol% of all the structural units of the resin. On a basis, it is generally 10 to 95 mol%, preferably 15 to 90 mol%, more preferably 20 to 85 mol%, particularly preferably 25 to 60 mol%.

Other examples of monomers having acid-labile groups include monomers represented by formula a1-3:

In Chemical Formula a1-3,

R ^a9 is a hydrogen atom, a C1-C3 alkyl group, a carboxyl group, a cyano group or a -COOR ^a13 group which may have one or more hydroxyl groups, wherein R ^a13 is a C1-C8 alkyl group or a C3-C20 alicyclic group A group consisting of a hydrocarbon group and a C1-C8 alkyl group and a C3-C20 cycloaliphatic hydrocarbon group, wherein the alkyl group and the cycloaliphatic hydrocarbon group may have one or more hydroxyl groups, and the alkyl group and the cycloaliphatic hydrocarbon group One or more of -CH ₂ -can be replaced by -O- or -CO-,

R ^a10 , R ^a11 and R ^a12 are each independently a C1-C12 alkyl group or a C3-C20 alicyclic hydrocarbon group, or R ^a10 and R ^a11 are bonded to each other to form C3 together with a carbon atom having R ^a10 and R ^a11 bonded thereto; May form a -C20 ring, the alkyl group and the cycloaliphatic hydrocarbon group may have one or more hydroxyl groups, and one or more of the alkyl group and the cycloaliphatic hydrocarbon group -CH ₂ -is -O- or May be replaced by -CO-.

Examples of C1-C3 alkyl groups which may have one or more hydroxyl groups include methyl groups, ethyl groups, propyl groups, hydroxymethyl groups and 2-hydroxyethyl groups. Examples of R ^a13 include a methyl group, ethyl group, propyl group, 2-oxo-oxolan-3-yl group and 2-oxo-oxolan-4-yl group. Examples of R ^a10 , R ^a11 and R ^a12 include methyl group, ethyl group, cyclohexyl group, methylcyclohexyl group, hydroxycyclohexyl group, oxocyclohexyl group and adamantyl group, and R ^a10 and R ^a11 Examples of the C3-C20 ring which are bonded to each other and formed together with the carbon atom to which R ^a10 and R ^a11 are bonded include a cyclohexane ring and an adamantane ring.

Examples of the monomer represented by Chemical Formula a1-3 include tert-butyl 5-norbornene-2-carboxylate, 1-cyclohexyl-1-methylethyl 5-norbornene-2-carboxylate, 1-methyl Cyclohexyl 5-norbornene-2-carboxylate, 2-methyl-2-adamantyl 5-norbornene-2-carboxylate, 2-ethyl-2-adamantyl 5-norbornene-2- Carboxylate, 1- (4-methylcyclohexyl) -1-methylethyl 5-norbornene-2-carboxylate, 1- (4-hydroxycyclohexyl) -1-methylethyl 5-norbornene-2 -Carboxylate, 1-methyl-1- (4-oxocyclohexyl) ethyl 5-norbornene-2-carboxylate and 1- (1-adamantyl) -1-methylethyl 5-norbornene-2 Carboxylates.

When the resin has structural units derived from the monomer represented by the formula a1-3, photoresist compositions having excellent resolution and higher dry-etch resistance tend to be obtained.

When the resin contains a structural unit derived from the monomer represented by the formula a1-3, the content of the structural unit derived from the monomer represented by the formula a1-3 is based on the total moles of all the structural units of the resin. Generally, it is 10 to 95 mol%, preferably 15 to 90 mol%, more preferably 20 to 85 mol%.

Another example of a monomer having an acid-labile group includes a monomer represented by Formula a1-4:

In Chemical Formula a1-4,

R ^a32 is a hydrogen atom, a halogen atom, a C1-C6 alkyl group or a C1-C6 halogenated alkyl group,

R ^a33 , at each occurrence, is independently a halogen atom, a hydroxyl group, a C1-C6 alkyl group, a C1-C6 alkoxy group, a C2-C4 acyl group, a C2-C4 acyloxy group, acryloyl group or methacryl Royle group,

la is an integer from 0 to 4,

R ^a34 and R ^a35 are each independently a hydrogen atom or a C1-C12 hydrocarbon group,

X ^a2 is a single bond or one or more -CH ₂ -is -O-, -CO-, -S-, -SO ₂ -or -N (R ^c )-, wherein R ^c is a hydrogen atom or C1-C6 C1-C17 divalent saturated hydrocarbon group which may be substituted by

Y ^a3 is a C1-C12 alkyl group, a C3-C18 alicyclic hydrocarbon group or a C6-C18 aromatic hydrocarbon group,

The C1-C17 divalent saturated hydrocarbon group, the C1-C12 alkyl group, the C3-C18 alicyclic hydrocarbon group and the C6-C18 aromatic hydrocarbon group are a halogen atom, hydroxyl group, C1-C6 alkyl group, C1-C6 It may have one or more substituents selected from the group consisting of alkoxy groups, C2-C4 acyl groups and C2-C4 acyloxy groups.

Examples of the halogen atom include fluorine atom, chlorine atom, bromine atom and iodine atom.

Examples of the C1-C6 alkyl group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, secondary-butyl group, tert-butyl group, pentyl group and hexyl group, C1-C4 alkyl groups are preferred, C1-C2 alkyl groups are more preferred, and methyl groups are particularly preferred.

Examples of the C1-C6 halogenated alkyl group include trifluoromethyl group, pentafluoroethyl group, heptafluoropropyl group, heptafluoroisopropyl group, nonafluorobutyl group, and nonafluorosecondary-butyl group , Nonafluoro tert-butyl group, perfluoropentyl group, perfluorohexyl group, perchloromethyl group, perbromomethyl group and periodomethyl group.

Examples of the C1-C6 alkoxy group include methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, isobutoxy group, secondary-butoxy group, tert-butoxy group, pentyloxy Groups and hexyloxy groups are included, C 1 -C 4 alkoxy groups are preferred, C 1 -C 2 alkoxy groups are more preferred, and methoxy groups are particularly preferred.

Examples of the C2-C4 acyl group include an acetyl group, propionyl group and butyryl group, and examples of the C2-C4 acyloxy group include an acetyloxy group, propionyloxy group and butyryloxy group.

Examples of the C1-C12 hydrocarbon group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, secondary-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, C1-C12 alkyl groups such as octyl group, 2-ethylhexyl group, nonyl group, decyl group, undecyl group and dodecyl group, and cyclohexyl group, adamantyl group, 2-alkyl-2-adamantyl group , C3-C12 alicyclic hydrocarbon group such as 1- (1-adamantyl) -1-alkyl group and isobornyl group, C6-C12 aromatic hydrocarbon group and group formed by combining at least one of the above-mentioned groups This includes.

Examples of the C1-C17 divalent saturated hydrocarbon group include methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6 -Diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decan-1,10-diyl group, undecane-1,11-diyl group, Dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group and C1-C17 alkanediyl groups such as heptadecane-1,17-diyl groups are included.

Examples of the C1-C12 alkyl group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, secondary-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, Octyl group, 2-ethylhexyl group, nonyl group, decyl group, undecyl group and dodecyl group. Examples of the C3-C18 alicyclic hydrocarbon group include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, norbornyl group, 1- Adamantyl group, 2-adamantyl group, isobornyl group and the following groups:

Examples of the C6-C18 aromatic hydrocarbon group include phenyl group, naphthyl group, anthryl group, p-methylphenyl group, p-tert-butylphenyl group and p-adamantylphenyl group.

Preferred substituents of X ^a2 and Y ^a3 are hydroxyl groups.

R ^a32 is preferably a C1-C4 alkyl group, more preferably a methyl group or an ethyl group, particularly more preferably a methyl group. R ^a33 is preferably a C1-C4 alkyl group or a C1-C4 alkoxy group, more preferably a methyl group, an ethyl group, a methoxy group or an ethoxy group, and even more preferably a methyl group or a methoxy group.

R ^a34 is preferably isopropyl group, butyl group, secondary-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group, 2-ethylhexyl group, cyclohexyl group, adamantyl group, 2 -Alkyl-2-adamantyl group, 1- (adamantan-1-yl) -1-alkyl group and isobornyl group. R ^a35 is preferably isopropyl group, butyl group, secondary-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group, 2-ethylhexyl group, cyclohexyl group, adamantyl group, 2 -Alkyl-2-adamantyl group, 1- (adamantan-1-yl) -1-alkyl group and isobornyl group.

Examples of the monomer represented by Chemical Formula a1-4 include the following ones.

When the resin contains a structural unit derived from the monomer represented by the formula a1-4, the content of the structural unit derived from the monomer represented by the formula a1-4 is based on the total moles of all the structural units of the resin. Generally, it is 10 to 95 mol%, preferably 15 to 90 mol%, more preferably 20 to 85 mol%.

Another example of a monomer having an acid-labile group includes the following:

Another example of a monomer having an acid-labile group includes a monomer represented by formula a1-5:

In Chemical Formula a1-5,

R ³¹ is a C1-C4 alkyl group which may be substituted with a hydrogen atom, a halogen atom, or a halogen atom,

L ⁵ is -O-, -S- or * -O- (CH ₂ ) _k1 -CO-O-, where k1 is an integer from 1 to 7 and * represents a binding position to -CO- ,

L ³ and L ⁴ are each independently -O- or -S-,

Z ¹ is a single bond, * — (CH ₂ ) _{n 4} —O— or — (CH ₂ ) _{n 4} —CO—O—, where n 4 is an integer from 1 to 4 and * represents a bonding position to L ⁵ . )ego,

s1 and s2 are each independently an integer of 0-4.

R ³¹ is preferably a hydrogen atom, a methyl group or a trifluoromethyl group, more preferably a hydrogen atom or a methyl group.

L ⁵ is preferably -O- or -S-, more preferably -O-.

It is preferred that any one of L ³ and L ⁴ is -O- and the other is -S-.

n4 is preferably 1;

In the formula a1-5, s1 is preferably 1, and s2 is preferably 0, 1 or 2.

Z ¹ is preferably a single bond or —CH ₂ —CO—O—.

Examples of the monomer represented by Chemical Formula a1-5 include the following ones.

When the resin contains a structural unit derived from the monomer represented by the formula a1-5, the content of the structural unit derived from the monomer represented by the formula a1-5 is based on the total moles of all the structural units of the resin. Generally, 1 to 95 mol%, preferably 3 to 90 mol%, more preferably 5 to 85 mol%.

The resin may have two or more structural units derived from monomers having acid-labile groups.

The resin preferably contains structural units derived from monomers having acid-labile groups and structural units derived from monomers having no acid-labile groups. The resin may have two or more structural units derived from monomers having no acid-labile groups. When the resin contains structural units derived from monomers having acid-labile groups and structural units derived from monomers having no acid-labile groups, the content of structural units derived from monomers having acid-labile groups is , Based on the total moles of all structural units of the resin, generally from 10 to 80 mole%, preferably from 20 to 60 mole%, and the content of structural units derived from monomers having no acid-labile groups, Based on the total moles of all the structural units of the resin, it is generally 90 to 20 mol%, preferably 80 to 40 mol%. In structural units derived from compounds having no acid-labile groups, the content of structural units derived from monomers having adamantyl groups, in particular monomers represented by the formula (a1-1), may affect the dry etching resistance of the photoresist composition. When considered, it is preferably 15 mol% or more.

Monomers having no acid-labile groups preferably contain one or more hydroxyl groups or lactone rings. When the resin does not have acid-labile groups and contains structural units derived from monomers containing at least one hydroxyl group or lactone ring, a photoresist composition having good resolution and adhesion of the photoresist to the substrate is obtained. There is a tendency.

Examples of monomers having no acid-labile groups and having at least one hydroxyl group include monomers represented by formula a2-0 and monomers represented by formula a2-1:

In Chemical Formula a2-0,

R ^a30 is a hydrogen atom, a halogen atom, a C1-C6 alkyl group or a C1-C6 halogenated alkyl group,

R ^a31 is independently at each occurrence a halogen atom, a hydroxyl group, a C1-C6 alkyl group, a C1-C6 alkoxy group, a C2-C4 acyl group, a C2-C4 acyloxy group, acryloyl group or methacryl Royle group,

ma is an integer of 0-4.

In Chemical Formula a2-1,

R ^a14 is a hydrogen atom or a methyl group,

R ^a15 and R ^a16 are each independently a hydrogen atom, a methyl group or a hydroxyl group,

L ^a3 is * -O- or * -O- (CH ₂ ) _k2 -CO-O-, where * represents a bonding position to -CO- and k2 is an integer of 1 to 7,

o1 is an integer of 0-10.

When using a KrF excimer laser (wavelength: 248 nm) lithography system or a high energy laser such as an electron beam and extreme ultraviolet rays as the exposure system, a resin containing a structural unit derived from the monomer represented by the formula (a2-0) When using an ArF excimer laser (wavelength: 193 nm) as an exposure system, resin containing the structural unit derived from the monomer represented by the said general formula (a2-1) is preferable.

In Chemical Formula a2-0, examples of the halogen atom include a fluorine atom, and examples of the C1-C6 alkyl group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, and secondary- Butyl groups, tert-butyl groups, pentyl groups and hexyl groups are included, C1-C4 alkyl groups are preferred, C1-C2 alkyl groups are more preferred, and methyl groups are particularly preferred. Examples of the C1-C6 halogenated alkyl group include trifluoromethyl group, pentafluoroethyl group, heptafluoropropyl group, heptafluoroisopropyl group, nonafluorobutyl group, and nonafluorosecondary-butyl group , Nonafluoro tert-butyl group, perfluoropentyl group and perfluorohexyl group. Examples of the C1-C6 alkoxy group include methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, isobutoxy group, secondary-butoxy group, tert-butoxy group, pentyloxy Groups and hexyloxy groups are included, C 1 -C 4 alkoxy groups are preferred, C 1 -C 2 alkoxy groups are more preferred, and methoxy groups are particularly preferred. Examples of the C2-C4 acyl group include an acetyl group, propionyl group and butyryl group, and examples of the C2-C4 acyloxy group include an acetyloxy group, propionyloxy group and butyryloxy group. In the formula a2-0, ma is preferably 0, 1 or 2, more preferably 0 or 1, particularly preferably 0.

The resin containing the structural unit derived from the monomer represented by the formula (a2-0) is, for example, a monomer obtained by protecting the hydroxyl group of the monomer represented by the formula (a2-0) with a protecting group such as an acetyl group. After polymerization, the obtained polymer can be prepared by deprotection with an acid or a base.

Examples of the monomer represented by the formula a2-0 include monomers described in JP 2010-204646 A, and 4-hydroxystyrene and 4-hydroxy-α-methylstyrene are preferable.

When the resin contains a structural unit derived from the monomer represented by the formula a2-0, the content of the structural unit derived from the monomer represented by the formula a2-0 is based on the total moles of all the structural units of the resin. Generally, 5 to 95 mol%, preferably 10 to 80 mol%, more preferably 15 to 80 mol%.

In Formula 2a-1, R ^a14 is preferably a methyl group, R ^a15 is preferably a hydrogen atom, R ^a16 is preferably a hydrogen atom or a hydroxyl group, and L ^a3 is preferably * -O Or * -O- (CH ₂ ) _f2 -CO-O-, where * represents a bonding position to -CO- and f2 is an integer from 1 to 4, more preferably * -O- is preferably 0, 1, 2 or 3, more preferably 0 or 1.

Examples of the monomer represented by Chemical Formula a2-1 include monomers described in JP 2010-204646 A, monomers represented by Chemical Formulas a2-1-1 to a2-1-6 are preferable, and Chemical Formula a2- More preferred are monomers represented by 1-1 to a2-1-4, and even more preferred are monomers represented by the formulas a2-1-1 and a2-1-3.

When the resin contains a structural unit derived from the monomer represented by the formula a2-1, the content of the structural unit derived from the monomer represented by the formula a2-1 is based on the total moles of all the structural units of the resin. Generally, 3 to 45 mol%, preferably 5 to 40 mol%, more preferably 5 to 35 mol%, particularly preferably 5 to 20 mol%.

Examples of lactone rings of monomers having no acid-labile groups and having lactone rings include monocyclic lactone rings such as β-propiolactone rings, γ-butyrolactone rings and γ-valerolactone rings, and monocyclic lactone rings; Condensed rings formed from other rings. Among them, a γ-butyrolactone ring and a condensed lactone ring formed from a γ-butyrolactone ring and other rings are preferable.

Preferred examples of monomers having no lact groups and having no acid-labile groups include those represented by the formulas a3-1, a3-2 and a3-3:

In Chemical Formulas a3-1 to a3-3,

L ^a4 , L ^a5 and L ^a6 are each independently * -O- or * -O- (CH ₂ ) _k3 -CO-O-, where * represents a bonding position to -CO-, and k3 is 1 to Is an integer of 7),

R ^a18 , R ^a19 and R ^a20 are each independently a hydrogen atom or a methyl group,

R ^a21 is a C1-C4 aliphatic hydrocarbon group,

R ^a22 and R ^a23 , at each occurrence, are independently a carboxyl group, cyano group or a C1-C4 aliphatic hydrocarbon group,

p1 is an integer from 0 to 5,

q1 and r1 are each independently an integer of 0-3.

L ^a4 , L ^a5 and L ^a6 each independently represent * -O- or * -O- (CH ₂ ) _d1 -CO-O-, where * represents a bonding position to -CO-, and d1 represents 1 to It is preferable that it is an integer of 4), and it is more preferable that L <^a4> , L <^a5> and L <^a6> are * -O-. R ^a18 , R ^a19 and R ^a20 are preferably methyl groups. R ^a21 is preferably a methyl group. R ^a22 and R ^a23 are each independently independently a carboxyl group, a cyano group or a methyl group. It is preferable that p1 is an integer of 0-2, and it is more preferable that p1 is 0 or 1. It is preferable that q1 and r1 are each independently an integer of 0-2, and it is more preferable that q1 and r1 are each independently 0 or 1.

Examples of the monomer represented by Chemical Formula a3-1 include monomers described in JP 2010-204646 A, and include Chemical Formulas a3-1-1 to a3-1-4 and a3-2-1 to a3-2-. Monomers represented by 4 and a3-3-1 to a3-3-4 are preferred, and monomers represented by the formulas a3-1-1 to a3-1-2 and a3-2-3 to a3-2-4 Are more preferred, and monomers represented by the formulas a3-1-1 and a3-2-3 are particularly preferred.

If the resin does not have acid-labile groups and contains structural units derived from monomers having lactone rings, the total content thereof is generally from 5 to 70 mole percent, based on the total moles of all structural units of the resin. , Preferably it is 10-65 mol%, More preferably, it is 10-60 mol%. The content of each structural unit derived from a monomer having no lact ring with no acid-labile groups is generally from 5 to 60 mole percent, preferably from 10 to 55, based on the total moles of all structural units of the resin. Mol%, more preferably 10 to 50 mol%.

Examples of another monomer having no acid-labile group include monomers represented by the formulas a4-1, a4-2 and a4-3:

In Chemical Formulas a4-1 to a4-3,

R ^a25 and R ^a26 each independently represent a hydrogen atom, a C1-C3 aliphatic hydrocarbon group, a carboxyl group, a cyano group or a -COOR ^a27 group, which may have one or more hydroxyl groups, wherein R ^a27 is a C1-C18 aliphatic hydrocarbon a group or a C3-C18 alicyclic hydrocarbon group, the C1-C18 aliphatic hydrocarbon group of at least one -CH ₂ group and the C3-C18 alicyclic hydrocarbon group - may be replaced by -O- or -CO-, stage , The carbon atom bonded to -O- of -COO- of R ^a27 is not a tertiary carbon atom), or R ^a25 and R ^a26 are bonded together, represented by -C (= O) -OC (= O)- To form a carboxylic anhydride residue.

Examples of the substituent of the C1-C3 aliphatic hydrocarbon group include a hydroxyl group. Examples of the C1-C3 aliphatic hydrocarbon group which may have one or more hydroxyl groups include C1-C3 alkyl groups such as methyl groups, ethyl groups and propyl groups, and C1 such as hydroxymethyl groups and 2-hydroxyethyl groups -C3 hydroxyalkyl group is included. The C1-C18 aliphatic hydrocarbon group represented by R ^a27 is preferably a C1-C8 aliphatic hydrocarbon group, more preferably a C1-C6 aliphatic hydrocarbon group. The C3-C18 cycloaliphatic hydrocarbon group represented by R ^a27 is preferably a C4-C18 cycloaliphatic hydrocarbon group, more preferably a C4-C12 cycloaliphatic hydrocarbon group. Examples of R ^a27 include a methyl group, ethyl group, propyl group, 2-oxo-oxolan-3-yl group and 2-oxo-oxolan-4-yl group.

Examples of the monomer represented by Chemical Formula a4-3 include 2-norbornene, 2-hydroxy-5-norbornene, 5-norbornene-2-carboxylic acid, methyl 5-norbornene-2-carboxylate , 2-hydroxyethyl 5-norbornene-2-carboxylate, 5-norbornene-2-methanol and 5-norbornene-2,3-dicarboxylic acid anhydride.

When the resin contains structural units derived from monomers of the formula a4-1, a4-2 or a4-3, the content thereof is generally from 2 to 40 moles, based on the total moles of all the structural units of the resin. %, Preferably it is 3-30 mol%, More preferably, it is 5-20 mol%.

Examples of another monomer not having an acid-labile group include fluorine-containing monomers represented by the following formula.

among them,

5- (3,3,3-trifluoro-2-hydroxy-2- (trifluoromethyl) propyl) bicyclo [2.2.1] hept-2-yl acrylate,

5- (3,3,3-trifluoro-2-hydroxy-2- (trifluoromethyl) propyl) bicyclo [2.2.1] hept-2-yl methacrylate,

6- (3,3,3-trifluoro-2-hydroxy-2- (trifluoromethyl) propyl) bicyclo [2.2.1] hept-2-yl acrylate,

5- (3,3,3-trifluoro-2-hydroxy-2- (trifluoromethyl) propyl) bicyclo [2.2.1] hept-2-yl methacrylate,

4,4-bis (trifluoromethyl) -3-oxatricyclo [4.2.1.0 ^2,5 ] nonyl acrylate and

Preferred is 4,4-bis (trifluoromethyl) -3-oxatricyclo [4.2.1.0 ^2,5 ] nonyl methacrylate.

If the resin contains structural units derived from the fluorine-containing monomers described above, the content thereof is generally from 1 to 20 mol%, preferably from 2 to 15, based on the total moles of all the structural units of the resin. Mol%, more preferably 3 to 10 mol%.

Preferred resins are resins containing structural units derived from monomers having acid-labile groups, and structural units derived from monomers having no acid-labile groups, and more preferred resins are derived from monomers having acid-labile groups. Resins containing structural units and monomers having lactone rings and / or structural units derived from monomers having at least one hydroxyl group. The monomer having an acid-labile group is preferably a monomer represented by the formula (a1-1) or a monomer represented by the formula (a1-2), and more preferably a monomer represented by the formula (a1-1). The monomer having at least one hydroxyl group is preferably a monomer represented by the formula (a2-1), and the monomer having a lactone ring is preferably a monomer represented by the formula (a3-1).

The resin can be prepared according to known polymerization methods such as radical polymerization.

The resin generally has a weight-average molecular weight of at least 2,500, preferably at least 3,000. The resin generally has a weight-average molecular weight of 50,000 or less, preferably 30,000 or less. The weight-average molecular weight can be measured by gel permeation chromatography.

The content of the acid generator is generally 1 part by weight or more, preferably 3 parts by weight or more per 100 parts by weight of the resin. The content of the acid generator is generally 30 parts by weight or less, preferably 25 parts by weight or less per 100 parts by weight of the resin. The content of salt (I) is generally 1 part by weight or more, preferably 3 parts by weight or more per 100 parts by weight of the resin. The content of the acid generator is generally 30 parts by weight or less, preferably 25 parts by weight or less per 100 parts by weight of the resin.

The content of the resin in the photoresist composition of the present invention is generally at least 80% by weight, and generally at most 99% by weight, based on the sum of the solid components. As used herein, "solid component" means components in the photoresist composition excluding the solvent.

The photoresist composition of the present invention may contain a basic compound as a quencher. The basic compound has a characteristic capable of capturing an acid, in particular an acid generated from an acid generator by irradiation.

The basic compound is preferably a basic nitrogen-containing organic compound, examples of which include amine compounds and ammonium salts such as aliphatic amines and aromatic amines. Examples of such aliphatic amines include primary amines, secondary amines and tertiary amines. Examples of such aromatic amines include aromatic amines in which the aromatic ring has one or more amino groups, such as aniline, and heteroaromatic amines such as pyridine. Preferred examples thereof include aromatic amines represented by the formula (C2).

Formula C2

In Chemical Formula C2,

Ar ^c1 is an aromatic hydrocarbon group,

R ^c5 and R ^c6 are independently a hydrogen atom, an aliphatic hydrocarbon group, a saturated cyclic hydrocarbon group or an aromatic hydrocarbon group, wherein the aliphatic hydrocarbon group, the saturated cyclic hydrocarbon group and the aromatic hydrocarbon group are a hydroxyl group, an amino group, One or two substituents selected from the group consisting of one or two C1-C4 alkyl groups, and C1-C6 alkoxy groups.

The aliphatic hydrocarbon group is preferably an alkyl group and the saturated cyclic hydrocarbon group is preferably a cycloalkyl group. The aliphatic hydrocarbon group preferably has 1 to 6 carbon atoms. The saturated cyclic hydrocarbon group preferably has 5 to 10 carbon atoms. The aromatic hydrocarbon group preferably has 6 to 10 carbon atoms.

As the aromatic amine represented by Chemical Formula C2, an amine represented by Chemical Formula C2-1 is preferable.

In Chemical Formula C2-1,

R ^c5 and R ^c6 are as defined above,

R ^c7 is independently at each occurrence an aliphatic hydrocarbon group, an alkoxy group, a saturated cyclic hydrocarbon group or an aromatic hydrocarbon group, wherein the aliphatic hydrocarbon group, the alkoxy group, the saturated cyclic hydrocarbon group and the aromatic hydrocarbon group are May have one or more substituents selected from the group consisting of a hydroxyl group, an amino group, an amino group having one or two C1-C4 alkyl groups, and a C1-C6 alkoxy group,

m3 is an integer of 0-3.

The aliphatic hydrocarbon group is preferably an alkyl group and the saturated cyclic hydrocarbon group is preferably a cycloalkyl group. The aliphatic hydrocarbon group preferably has 1 to 6 carbon atoms. The saturated cyclic hydrocarbon group preferably has 5 to 10 carbon atoms. The aromatic hydrocarbon group preferably has 6 to 10 carbon atoms. The alkoxy group preferably has 1 to 6 carbon atoms.

Examples of the aromatic amine represented by the formula (C2) include 1-naphthylamine, 2-naphthylamine, aniline, diisopropylaniline, 2-methylaniline, 3-methylaniline, 4-methylaniline, 4-nitroaniline, N-methylaniline, N, N-dimethylaniline and diphenylamine are included, among these, diisopropylaniline is preferable and 2,6-diisopropylaniline is more preferable.

Other examples of the basic compound include amines represented by the formulas C3 to C11.

In Chemical Formulas C3 to C11,

R ^c8 , R ^c20 , R ^c21 , and R ^c23 to R ^c28 are independently an aliphatic hydrocarbon group, an alkoxy group, a saturated cyclic hydrocarbon group or an aromatic hydrocarbon group, and the aliphatic hydrocarbon group, the alkoxy group, the saturated cyclic hydrocarbon Group and said aromatic hydrocarbon group may have one or more substituents selected from the group consisting of a hydroxyl group, an amino group, an amino group having one or two C1-C4 alkyl groups, and a C1-C6 alkoxy group,

R ^c9 , R ^c10 , R ^c11 to R ^c14 , R ^c16 to R ^c19 , and R ^c22 are independently a hydrogen atom, an aliphatic hydrocarbon group, a saturated cyclic hydrocarbon group or an aromatic hydrocarbon group, and the aliphatic hydrocarbon group, between the saturation The click hydrocarbon group and the aromatic hydrocarbon group may have one or more substituents selected from the group consisting of a hydroxyl group, an amino group, an amino group having one or two C1-C4 alkyl groups, and a C1-C6 alkoxy group ,

R ^c15 , at each occurrence, is independently an aliphatic hydrocarbon group, a saturated cyclic hydrocarbon group or an alkanoyl group,

L ^c1 and L ^c2 are independently a divalent aliphatic hydrocarbon group, -CO-, -C (= NH)-, -C (= NR ^c3 )-, wherein R ^c3 is a C1-C4 alkyl group, -S -, -SS- or a combination thereof,

o3 to u3 are each independently an integer of 0 to 3,

n3 is an integer of 0-8.

The aliphatic hydrocarbon group preferably has 1 to 6 carbon atoms, the saturated cyclic hydrocarbon group preferably has 3 to 6 carbon atoms, and the alkanoyl group preferably has 2 to 6 carbon atoms And the divalent aliphatic hydrocarbon group preferably has 1 to 6 carbon atoms. The divalent aliphatic hydrocarbon group is preferably an alkylene group.

Examples of the amine represented by the formula (C3) are hexylamine, heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didide Silamine, triethylamine, trimethylamine, tripropylamine, tributylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentyl Amine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldi Heptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine, dicyclohexylmethylamine, tris [2- (2-methoxyethoxy) ethyl] amine, triisopropanolamine, ethylenediamine, tetramethylenediamine , Hexamethylenediamine, 4 , 4'-diamino-1,2-diphenylethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane and 4,4'-diamino-3,3'-diethyldiphenyl Methane is included.

Examples of the amine represented by the formula C4 include piperazine. Examples of the amine represented by the formula C5 include morpholine. Examples of the amine represented by the above formula (C6) include piperidine, and a hindered amine compound having a piperidine skeleton as described in JP 11-52575 A. Examples of the amine represented by the formula C7 include 2,2'-methylenebisaniline. Examples of the amine represented by the formula C8 include imidazole and 4-methylimidazole. Examples of the amine represented by the formula C9 include pyridine and 4-methylpyridine. Examples of the amine represented by Formula C10 include di-2-pyridyl ketone, 1,2-di (2-pyridyl) ethane, 1,2-di (4-pyridyl) ethane, 1,3-di ( 4-pyridyl) propane, 1,2-bis (2-pyridyl) ethene, 1,2-bis (4-pyridyl) ethene, 1,2-di (4-pyridyloxy) ethane, 4,4 '-Dipyridyl sulfide, 4,4'-dipyridyl disulfide, 2,2'-dipyridylamine and 2,2'-dipicolylamine. Examples of the amine represented by the formula C11 include bipyridine.

Examples of quaternary ammonium hydroxides include tetramethylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, (3-trifluoro Methylphenyl) trimethylammonium hydroxide and (2-hydroxyethyl) trimethylammonium hydroxide (so-called "choline").

Among these, diisopropyl aniline is preferable and 2,6-diisopropyl aniline is more preferable.

When the photoresist composition contains a basic compound, its content is generally 0.01 to 1% by weight based on the total amount of solid components. The content of the basic compound is preferably less than the total content of acid generators other than salt (I) and salt (I).

Photoresist compositions of the invention generally contain one or more solvents. Examples of such solvents include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate and propylene glycol monomethyl ether acetate; Glycol ethers such as propylene glycol monomethyl ether; Acyclic esters such as ethyl lactate, butyl acetate, amyl acetate and ethyl pyruvate; Ketones such as acetone, methyl isobutyl ketone, 2-heptanone and cyclohexanone; And cyclic esters such as γ-butyrolactone.

The amount of the solvent is generally at least 90% by weight, preferably at least 92% by weight, more preferably at least 94% by weight, based on the total amount of the photoresist composition of the present invention. The amount of the solvent is generally 99.9% by weight or less, preferably 99% by weight or less, based on the total amount of the photoresist composition of the present invention. If the photoresist composition contains a solvent in this amount, a photoresist layer of about 30 to about 300 nm in thickness can be readily produced.

The photoresist composition of the present invention may contain small amounts of various additives such as sensitizers, dissolution inhibitors, other polymers, surfactants, stabilizers and dyes, as needed, so long as they do not interfere with the effects of the present invention.

The photoresist composition of the present invention is useful for chemically amplified photoresist compositions.

The photoresist pattern may be prepared by the following steps (1) to (5):

(1) applying the first or second photoresist composition of the present invention onto a substrate,

(2) drying to form a photoresist film,

(3) exposing the photoresist film to radiation,

(4) baking the exposed photoresist film, and

(5) developing the baked photoresist film with an alkaline developer to form a photoresist pattern.

Applying the photoresist composition onto a substrate is generally performed using conventional devices such as spin coaters. Preferably the photoresist composition is filtered with a filter having a pore size of 0.01 to 0.2 μm prior to application. Examples of the substrate include a silicon wafer or a quartz wafer, on which a sensor, a circuit, a transistor, and the like are formed.

The formation of the photoresist film is generally carried out using a heating device or a decompressor such as a hot plate, the heating temperature is generally 50 to 200 ° C., and the operating pressure is generally 1 to 1.0 × 10 ⁵ Pa. .

The obtained photoresist film is exposed to radiation using an exposure system. Exposure is generally carried out through a mask having a pattern corresponding to the desired photoresist pattern. Examples of exposure sources include light sources that emit laser light in the ultraviolet region, such as KrF excimer laser (wavelength: 248 nm), ArF excimer laser (wavelength: 193 nm), and F ₂ laser (wavelength: 157 nm), and solid state laser light sources. And a light source (eg, YAG or semiconductor laser) for converting the wavelength of the laser light from the light to emit harmonic laser light in the far ultraviolet region or the vacuum ultraviolet region.

The baking temperature of the exposed photoresist film is generally 50 to 200 ° C, preferably 70 to 150 ° C.

The development of the baked photoresist film is generally carried out using a developing apparatus. The alkaline developer used may be any of various alkali aqueous solutions used in the art. Generally, aqueous solutions of tetramethylammonium hydroxide or (2-hydroxyethyl) trimethylammonium hydroxide (commonly known as "choline") are often used. After development, the formed photoresist pattern is preferably washed with ultrapure water, and water and the substrate remaining on the photoresist pattern are preferably removed.

The photoresist composition of the present invention provides a photoresist pattern exhibiting good exposure latitude (EL), whereby the photoresist composition of the present invention is an ArF excimer laser lithography, KrF excimer laser lithography, ArF immersion lithography (immersion) lithography), EUV (extreme ultraviolet) lithography, EUV immersion lithography and EB (electron beam) lithography. In addition, the photoresist compositions of the invention can be used in particular for EUV lithography and EB lithography.

Example

Although the present invention will be described in more detail by way of examples, these examples do not limit the scope of the invention.

"%" And "parts" used to indicate the amount of any ingredient and the amount of material used in the following examples and comparative examples are by weight unless otherwise specified. The weight-average molecular weight of any of the materials used in the examples below was determined by gel permeation chromatography [Column: 3 TSKgel Multipore HXL-M with Guard Column] using standard polystyrene (TOSOH CORPORATION) as the standard reference material. Manufacturer: TOSOH CORPORATION, solvent: tetrahydrofuran, flow rate: 1.0 ml / min, detector: RI detector, column temperature: 40 ° C., injection volume: 100 μl]. The structure of the compound was measured by a mass spectrometer [liquid chromatography: 1100 type, manufactured by AGILENT TECHNOLOGIES LTD., Mass spectrometer: LC / MSD type, manufactured by AGILENT TECHNOLOGIES LTD.]. The ratio of structural units in the resin was determined by measuring the amount of unreacted monomer in the reaction after polymerization, and then calculating the amount of reacted monomer from the measured result.

Example 1

The mixture containing 6.03 parts of salt of formula I1-a and 30.00 parts of acetonitrile was stirred at 23 ° C. for 30 minutes. To this mixture, 1.70 parts of salt of formula (I1-b) was added. The resulting mixture was stirred at 60 ° C. for 1 hour. The reaction mixture was filtered and the filtrate obtained was concentrated. To the obtained concentrate, 30 parts of chloroform and 15 parts of ion-exchanged water were added, and the obtained mixture was stirred at 23 ° C. for 30 minutes and then separated to obtain an organic layer. The organic layer was mixed with 15 parts of ion-exchanged water, stirred at 23 ° C. for 30 minutes, and then separated to obtain an organic layer. This wash was performed three more times. The obtained organic layer was mixed with 1.00 parts of activated carbon, and the obtained mixture was stirred at 23 ° C. for 30 minutes and then filtered. The filtrate obtained was concentrated. The resulting concentrate was mixed with 100 parts of tert-butyl methyl ether and the resulting mixture was stirred and filtered to give 6.12 parts of salt of formula (I1-c).

A mixture containing 5.00 parts of salt of formula (I1-c), 30.00 parts of N, N-dimethylformamide and 1.37 parts of compound of formula (I1-d) was stirred at 23 ° C. for 30 minutes. To this mixture, 0.10 part of potassium carbonate was added, and the obtained mixture was stirred at 23 ° C. for 2 hours. To the obtained reaction mixture, 60 parts of chloroform and 20 parts of ion-exchanged water were added, followed by stirring and separation to obtain an organic layer. The organic layer obtained was washed six times with ion-exchanged water. The obtained organic layer was mixed with 1.00 parts of activated carbon, and the obtained mixture was stirred at 23 ° C. for 30 minutes and then filtered. The filtrate obtained was concentrated. The resulting concentrate was mixed with 20 parts of acetonitrile and the solution obtained was concentrated. The residue was mixed with 50 parts of tert-butyl methyl ether and the resulting mixture was stirred and then the supernatant was removed. The residue obtained was dissolved in chloroform and the solution obtained was concentrated. The residue obtained was purified by silica gel column chromatography (silica gel 60-200 mesh, commercially available from Merck KGaA, solvent: chloroform / methanol = 5: 1) to give 2.48 parts of the salt of formula (I1). This is called salt I1.

MS (ESI (+) Spectrum): M ⁺ 263.1

MS (ESI (-) Spectrum): M ^- 547.2

Example 2

Salts of formula (I2-a) were prepared according to the method described in JP 2008-127367 A. A mixture containing 50.00 parts of salt of formula (I2-a), 300 parts of chloroform and 20.34 parts of compound of formula (I2-b) was stirred at 23 ° C. for 30 minutes. The mixture was heated to 60 ° C. and then stirred for 1 hour. The obtained reaction mixture was cooled to 23 ° C., to which 28.31 parts of ethylene glycol was added and stirred at 23 ° C. for 3 hours. To the obtained mixture, 200 parts of chloroform and 75 parts of ion-exchanged water were added, and the obtained mixture was stirred and separated to obtain an organic layer. This wash was performed four times. The obtained organic layer was mixed with 1.00 parts of activated carbon, and the obtained mixture was stirred at 23 ° C. for 30 minutes and then filtered. The filtrate obtained was concentrated. The resulting concentrate was mixed with 80 parts of acetonitrile. The obtained solution was concentrated, the obtained residue was mixed with 150 parts of tert-butyl methyl ether, and the obtained mixture was stirred and filtered to give 24.58 parts of a salt of formula I2-d.

A mixture containing 20.00 parts of compound of formula I2-e, 140 parts of chloroform and 19.57 parts of compound of formula I2-b was stirred at 23 ° C. for 1 hour. The obtained reaction mixture was mixed with 50 parts of ion-exchanged water, stirred and separated to obtain an organic layer. The organic layer was washed five times with ion-exchanged water. The obtained organic layer was mixed with 1.00 parts of activated carbon, and the obtained mixture was stirred at 23 ° C. for 30 minutes and then filtered. The filtrate obtained was concentrated. The resulting concentrate was mixed with 100 parts of tert-butyl methyl ether and the resulting mixture was stirred and filtered to give 24.94 parts of compound of formula I2-f.

A mixture containing 5.00 parts of salt of formula I2-d, 30.00 parts of N, N-dimethylformamide and 3.01 parts of compound of formula I2-f was stirred at 23 ° C. for 30 minutes. To this mixture, 0.14 parts of potassium carbonate was added, and the obtained mixture was stirred at 40 ° C. for 2 hours. To the obtained reaction mixture, 80 parts of chloroform and 30 parts of ion-exchanged water were added, followed by stirring and separation to obtain an organic layer. The organic layer obtained was washed eight times with ion-exchanged water. The obtained organic layer was mixed with 1.00 parts of activated carbon, and the obtained mixture was stirred at 23 ° C. for 30 minutes and then filtered. The filtrate obtained was concentrated. The resulting concentrate was mixed with 20 parts of acetonitrile and the solution obtained was concentrated. The residue was mixed with 50 parts of tert-butyl methyl ether and the resulting mixture was stirred and then the supernatant was removed. The residue obtained was dissolved in chloroform and the solution obtained was concentrated. The residue obtained was purified by silica gel column chromatography (silica gel: 60-200 mesh silica gel, available from Merck KGaA, solvent: chloroform / methanol = 5: 1) to give 4.02 parts of salt of formula (I2). This is called salt I2.

MS (ESI (+) Spectrum): M ⁺ 263.1

MS (ESI (-) Spectrum): M ^- 427.1

Example 3

The mixture containing 10.4 parts of lithium aluminum hydride and 120 parts of anhydrous tetrahydrofuran was stirred at 23 ° C. for 30 minutes. To the mixture, a solution prepared by dissolving 62.2 parts of the salt of formula I3-a in 900 parts of anhydrous tetrahydrofuran was added dropwise under ice cooling, and the obtained mixture was stirred at 23 ° C. for 5 hours. The obtained reaction mixture was mixed with 50 parts of ethyl acetate and 50.00 parts of 6N hydrochloric acid, followed by separation to obtain an organic layer. The organic layer obtained was concentrated and the residue obtained was purified by silica gel column chromatography (silica gel: 60-200 mesh silica gel, available from Merck KGaA, solvent: chloroform / methanol = 5: 1) to formula (I3). 84.7 parts of a salt of -b were obtained (purity: 60%).

A mixture containing 6.13 parts of salt of formula I3-b, 100 parts of chloroform and 5.98 parts of salt of formula I3-c was stirred at 23 ° C. for 3 hours. 50 parts of ion-exchanged water was added to the obtained reaction mixture and washed to obtain an organic layer. This wash was performed three times. The obtained organic layer was mixed with 1.00 parts of activated carbon, and the obtained mixture was stirred at 23 ° C. for 30 minutes and then filtered. The filtrate obtained was concentrated. The resulting concentrate was mixed with 100 parts of acetonitrile and the solution obtained was concentrated. The residue was mixed with 100 parts of ethyl acetate and the resulting mixture was stirred and then the supernatant was removed. 100 parts of tert-butyl methyl ether was added to the obtained residue, and the obtained mixture was stirred, then the supernatant was removed. The residue obtained was dissolved in chloroform and the solution obtained was concentrated. The residue obtained was purified by silica gel column chromatography (silica gel 60-200 mesh, commercially available from Merck KGaA, solvent: chloroform / methanol = 5: 1) to obtain 4.96 parts of a salt of formula I3-d. .

A mixture containing 4.40 parts of salt of formula I3-d, 30.00 parts of N, N-dimethylformamide and 3.01 parts of compound of formula I2-f was stirred at 23 ° C. for 30 minutes. To this mixture, 0.14 parts of potassium carbonate was added, and the obtained mixture was stirred at 40 ° C. for 2 hours. To the obtained reaction mixture, 80 parts of chloroform and 30 parts of ion-exchanged water were added, followed by stirring and separation to obtain an organic layer. The organic layer obtained was washed eight times with ion-exchanged water. The obtained organic layer was mixed with 1.00 parts of activated carbon, and the obtained mixture was stirred at 23 ° C. for 30 minutes and then filtered. The filtrate obtained was concentrated. The resulting concentrate was mixed with 20 parts of acetonitrile and the solution obtained was concentrated. The residue was mixed with 50 parts of tert-butyl methyl ether and the resulting mixture was stirred and then the supernatant was removed. The residue obtained was dissolved in chloroform and the solution obtained was concentrated. The residue obtained was purified by silica gel column chromatography (silica gel 60-200 mesh, commercially available from Merck KGaA, solvent: chloroform / methanol = 5: 1) to give 0.52 parts of the salt of formula (I3). This is called salt I3.

MS (ESI (+) Spectrum): M ⁺ 263.1

MS (ESI (-) Spectrum): M ^- 369.1

Example 4

A mixture containing 5.00 parts of salt of formula (I1-c), 30.00 parts of N, N-dimethylformamide and 0.87 parts of compound of formula (I83-d) was stirred at 23 ° C. for 30 minutes. To this mixture, 0.10 part of potassium carbonate was added, and the obtained mixture was stirred at 23 ° C. for 2 hours. To the obtained reaction mixture, 60 parts of chloroform and 20 parts of ion-exchanged water were added, followed by stirring and separation to obtain an organic layer. The organic layer obtained was washed six times with ion-exchanged water. The obtained organic layer was mixed with 0.80 parts of activated carbon, and the obtained mixture was stirred at 23 ° C. for 30 minutes and then filtered. The filtrate obtained was concentrated. The resulting concentrate was mixed with 20 parts of acetonitrile and the solution obtained was concentrated. The residue was mixed with 50 parts of tert-butyl methyl ether and the resulting mixture was stirred and then the supernatant was removed. The residue obtained was dissolved in chloroform and the solution obtained was concentrated to give 3.48 parts of the salt of formula I83. This is called salt I83.

MS (ESI (+) Spectrum): M ⁺ 263.1

MS (ESI (-) Spectrum): M ^- 481.1

Example 5

A mixture containing 5.00 parts of salt of formula (I1-c), 30.00 parts of N, N-dimethylformamide and 0.55 part of compound of formula (I84-d) was stirred at 23 ° C. for 30 minutes. To this mixture, 0.10 part of potassium carbonate was added, and the obtained mixture was stirred at 23 ° C. for 2 hours. To the obtained reaction mixture, 60 parts of chloroform and 20 parts of ion-exchanged water were added, followed by stirring and separation to obtain an organic layer. The organic layer obtained was washed six times with ion-exchanged water. The obtained organic layer was mixed with 0.80 parts of activated carbon, and the obtained mixture was stirred at 23 ° C. for 30 minutes and then filtered. The filtrate obtained was concentrated. The resulting concentrate was mixed with 20 parts of acetonitrile and the solution obtained was concentrated. The residue was mixed with 50 parts of tert-butyl methyl ether and the resulting mixture was stirred and then the supernatant was removed. The residue obtained was dissolved in chloroform and the solution obtained was concentrated to give 2.24 parts of salt of formula (I84). This is called salt I84.

MS (ESI (+) Spectrum): M ⁺ 263.1

MS (ESI (-) Spectrum): M ^- 439.1

Example 6

A mixture containing 3.00 parts of salt of formula (I1-c), 25.00 parts of acetone, 0.98 parts of compound of formula (I85-d) and 0.10 part of potassium carbonate was stirred at 50 ° C. for 20 hours. The reaction mixture obtained was concentrated. 36 parts of chloroform and 12 parts of ion-exchanged water were added to the obtained concentrate, followed by stirring and separation to obtain an organic layer. The organic layer obtained was washed six times with ion-exchanged water. The obtained organic layer was mixed with 0.50 part of activated carbon, and the obtained mixture was stirred at 23 ° C. for 30 minutes and then filtered. The filtrate obtained was concentrated. The resulting concentrate was mixed with 50 parts of tert-butyl methyl ether. The resulting mixture was stirred and filtered. The residue obtained was dissolved in acetonitrile and the solution obtained was concentrated. The obtained residue was mixed with 15 parts of ethyl acetate and then filtered to obtain 1.58 parts of a salt of formula (I85). This is called salt I85.

MS (ESI (+) Spectrum): M ⁺ 263.1

MS (ESI (-) Spectrum): M ^- 555.1

The monomers used in Resin Synthesis Examples 1 to 2 are the following monomers A, B, C, D, E, F and G.

Resin Synthesis Example 1

The monomers D, E, B, C and F are mixed in a molar ratio of 30/14/6/20/30 (monomer D / monomer E / monomer B / monomer C / monomer F) and based on the total parts of all monomers is 1.5 1,4-dioxane was added in portions of the vessel to prepare a mixture. In the mixture, azobisisobutyronitrile in 1 mole% based on the molar amount of all monomers as initiator and azobis (2,4-dimethylvaleronitrile in 3 mole% based on molar amount of all monomers as initiator. ) Was added and the resulting mixture was heated to 73 ° C. for about 5 hours. The obtained reaction mixture was poured into a large amount of a mixture of methanol and water (weight ratio = 4/1) to cause precipitation. The precipitate was collected by filtration, then dissolved in 1,4-dioxane, and the resulting solution was poured into a large amount of a mixture of methanol and water to cause precipitation, and the precipitate was collected by filtration. This operation was repeated twice for purification. As a result, a resin having a weight average molecular weight of about 8.1 × 10 ³ was obtained in a yield of 65%. This resin is called Resin A1. Resin A1 has the following structural units.

Resin Synthesis Example 2

Monomers A, E, B, C and F are mixed in a molar ratio of 30/14/6/20/30 (monomer A / monomer E / monomer B / monomer C / monomer F) and based on the total parts of all monomers is 1.5 1,4-dioxane was added in portions of the vessel to prepare a mixture. In the mixture, azobisisobutyronitrile in 1 mole% based on the molar amount of all monomers as initiator and azobis (2,4-dimethylvaleronitrile in 3 mole% based on molar amount of all monomers as initiator. ) Was added and the resulting mixture was heated to 73 ° C. for about 5 hours. The obtained reaction mixture was poured into a large amount of a mixture of methanol and water (weight ratio = 4/1) to cause precipitation. The precipitate was collected by filtration, then dissolved in 1,4-dioxane, and the resulting solution was poured into a large amount of a mixture of methanol and water to cause precipitation, and the precipitate was collected by filtration. This operation was repeated three times for purification. As a result, a resin having a weight average molecular weight of about 7.8 × 10 ³ was obtained in a yield of 68%. This resin is called Resin A2. Resin A2 has the following structural units.

Resin Synthesis Example 3

The mixtures were mixed by mixing monomers A, B and C in a molar ratio of 50/25/25 (monomer A / monomer B / monomer C) and adding 1,4-dioxane in 1.5-fold parts based on the total parts of all monomers. Prepared. In the mixture, azobisisobutyronitrile in 1 mole% based on the molar amount of all monomers as initiator and azobis (2,4-dimethylvaleronitrile in 3 mole% based on molar amount of all monomers as initiator. ) Was added and the resulting mixture was heated to 80 ° C. for about 8 hours. The obtained reaction mixture was poured into a large amount of a mixture of methanol and water (weight ratio = 4/1) to cause precipitation. The precipitate was collected by filtration, then dissolved in 1,4-dioxane, and the resulting solution was poured into a large amount of a mixture of methanol and water to cause precipitation, and the precipitate was collected by filtration. This operation was repeated three times for purification. As a result, a resin having a weight average molecular weight of about 9.2 × 10 ³ was obtained in a yield of 60%. This resin is called Resin A3. Resin A3 has the following structural units.

Resin Synthesis Example 4

Monomers A, E, B, F and C are mixed in a molar ratio of 30/14/6/20/30 (monomer A / monomer E / monomer B / monomer F / monomer C) and based on the total parts of all monomers is 1.5 1,4-dioxane was added in portions of the vessel to prepare a mixture. In the mixture, azobisisobutyronitrile in 1 mole% based on the molar amount of all monomers as initiator and azobis (2,4-dimethylvaleronitrile in 3 mole% based on molar amount of all monomers as initiator. ) Was added and the resulting mixture was heated to 75 ° C. for about 5 hours. The reaction mixture obtained was poured into a large amount of a mixture of methanol and water to cause precipitation. The precipitate was collected by filtration, then dissolved in 1,4-dioxane, and the resulting solution was poured into a large amount of a mixture of methanol and water to cause precipitation, and the precipitate was collected by filtration. This operation was repeated twice for purification. As a result, a resin having a weight average molecular weight of about 7.2 × 10 ³ was obtained in a yield of 78%. This resin is called Resin A4. Resin A4 has the following structural units.

Resin Synthesis Example 5

Monomers A, G, B, F and C are mixed in a molar ratio of 30/14/6/20/30 (monomer A / monomer G / monomer B / monomer F / monomer C) and based on the total parts of all monomers is 1.5 1,4-dioxane was added in portions of the vessel to prepare a mixture. In the mixture, azobisisobutyronitrile in 1 mole% based on the molar amount of all monomers as initiator and azobis (2,4-dimethylvaleronitrile in 3 mole% based on molar amount of all monomers as initiator. ) Was added and the resulting mixture was heated to 75 ° C. for about 5 hours. The reaction mixture obtained was poured into a large amount of a mixture of methanol and water to cause precipitation. The precipitate was collected by filtration, then dissolved in 1,4-dioxane, and the resulting solution was poured into a large amount of a mixture of methanol and water to cause precipitation, and the precipitate was collected by filtration. This operation was repeated twice for purification. As a result, a resin having a weight average molecular weight of about 7.2 × 10 ³ was obtained in a yield of 78%. This resin is called Resin A5. Resin A5 has the following structural units.

Examples 7-18 and Comparative Example 1

<Resin>

Resin A1, A2, A3, A4, A5

<Acid generator>

I1: salt I1

I2: salt I2

I3: salt I3

I83: salt I83

I84: salt I84

I85: salt I85

B1:

It was prepared according to the method described in JP 2010-152341 A.

B2:

It was prepared according to the method described in JP 2007-161707 A.

<Kenture>

C1: 2,6-diisopropylaniline

<Solvent>

E1: propylene glycol monomethyl ether acetate 265 parts

    20 parts propylene glycol monomethyl ether

    2-heptanone 20parts

    γ-butyrolactone 3.5 parts

The following components were mixed and dissolved, and then filtered through a fluorine resin filter having a pore diameter of 0.2 μm to prepare a photoresist composition.

Resin (Type and Amount are Listed in Table 6)

Acid Generators (Types and Amounts are Listed in Table 6)

Quenchers (types and amounts are listed in Table 6)

Solvent E1

The silicon wafers (12 inches) were each coated with an antireflective organic coating composition "ARC-29" manufactured by Nissan Chemical Industries, Ltd., and then baked at 205 DEG C for 60 seconds to prevent 78 nm thick antireflection. An organic coating was formed. Each photoresist composition prepared as above was spin coated onto the antireflective coating such that the final film thickness after drying was 85 nm. The silicon wafers thus coated with each photoresist composition were each prebaked for 60 seconds on a direct hotplate at the temperature described in the "PB" column of Table 6. The wafer having each of the resist films thus formed was subjected to immersion exposure using an ArF excimer stepper ("XT-1900Gi" manufactured by ASML, NA = 1.35, 3/4 annular, XY deflection) to change the exposure dose stepwise. It processed by line-and-space-pattern exposure. Ultrapure water was used as the immersion medium.

After exposure, each wafer is post-exposure baked for 60 seconds on a hotplate at the temperatures listed in the "PEB" column of Table 6, followed by paddles for 60 seconds using an aqueous 2.38 wt% tetramethylammonium hydroxide solution. ) To obtain a photoresist pattern.

Each pattern developed on the antireflective organic coated substrate after development was observed with a scanning electron microscope, and the results are shown in Table 7.

Effective sensitivity (ES): This is expressed as the exposure amount when the line width of the 50 nm line and space pattern becomes 1: 1 after exposure and development through the line and space pattern mask.

Line edge roughness (LER: line edge roughness): The exposure amount when the line width of the 50-resist pattern became a 1: 1 line-and-space pattern, that is, the photoresist pattern at the effective sensitivity was observed with a scanning electron microscope. The difference between the height of the highest point and the lowest point of the wall surface of the photoresist pattern was measured. If the difference is 3.5 nm or less, the LER is very good and its evaluation is expressed as "◎◎". If the difference is more than 3.5 nm and 4.0 nm or less, the LER is good and its evaluation is expressed as "◎", If the difference is more than 4.0 nm and less than or equal to 4.5 nm, the LER is normal and its evaluation is represented by "○", and when the difference is more than 4.5 nm, the LER is poor and its evaluation is represented by "x". In addition, each of these differences is also listed in parentheses in the "LER" column of Table 7. The smaller the difference, the better the pattern.

Salts of the present invention are suitable for acid generators, and photoresist compositions comprising the salts of the present invention provide a good photoresist pattern with good line edge roughness (LER).

Claims (13)

Salt represented by formula (I):
Formula I

In Formula I,
Q ¹ and Q ² are each independently a fluorine atom or a C1-C6 perfluoroalkyl group,
L ¹ is * -CO-OL ^1b1 -**, * -CO-OL ^1b3 -CO-OL ^1b2 -**, * -CO-OL ^1b5 -OL ^1b4 -** or * -L ^1b7 -OL ^1b6- * * Wherein L ^1b1 is a C1-C15 divalent saturated hydrocarbon group, L ^1b2 is a C1-C12 divalent saturated hydrocarbon group, and L ^1b3 is a C1-C12 divalent saturated hydrocarbon group, provided that L ^1b2 and L ^1b3 Has 1 to 13 carbon atoms, L ^1b4 is a C1-C13 divalent saturated hydrocarbon group, L ^1b5 is a C1-C13 divalent saturated hydrocarbon group, provided that L ^1b4 and L ^1b5 are 1 to 14 , L ^1b6 is a C1-C15 divalent saturated hydrocarbon group, L ^1b7 is a C1-C15 divalent saturated hydrocarbon group, provided that L ^1b6 and L ^1b7 have 1 to 16 carbon atoms, and * is -C (Q ¹ Indicates a bonding position for) (Q ² )-, ** indicates a bonding position for -O-CO-OL ² -Y,
L ² is a single bond or a C1-C6 alkanediyl group, wherein one or more -CH ₂ -can be replaced by -O- or -CO-,
Y is a C3-C18 cycloaliphatic hydrocarbon group which may have one or more substituents, and one or more -CH ₂ -in the cycloaliphatic hydrocarbon group can be replaced by -O-, -CO- or -SO _2- ,
Z ⁺ is an organic counter ion. Salt represented by formula (I):
Formula I

In Formula I,
Q ¹ and Q ² are each independently a fluorine atom or a C1-C6 perfluoroalkyl group,
L ¹ is a C1-C17 divalent saturated hydrocarbon group, wherein one or more -CH ₂ -can be replaced by -O- or -CO-,
L ² is a single bond or a C1-C6 alkanediyl group, wherein one or more -CH ₂ -can be replaced by -O- or -CO-,
Y is any one of the formulas:

,

Represents the bonding position with respect to L ² ,
Z ⁺ is an organic counter ion. The salt of claim 1, wherein L ¹ is * -CO-OL ^1b1 -**. The salt according to claim 1, wherein L ¹ is * -CO-O-CH ₂ -CH ₂ -** or a group represented by the following formula:

. 3. The compound of claim 2, wherein L ¹ is a C1-C6 alkanediyl group or * -CO-OL ^b2 -** [where L ^b2 is a C1-C15 divalent saturated hydrocarbon group and * is -C (Q ¹ ) Indicates a binding position for (Q ² ) —, ** indicates a binding position for —O—CO—OL ² —Y]. 3. The compound of claim 2, wherein L ¹ is a methylene group, * —CO—O—CH ₂ —CH ₂ — ** [where * represents a binding position to —C (Q ¹ ) (Q ² ) — and * Represents a bonding position to —O—CO—OL ² —Y] or a group represented by the following formula:

In the above formula, * indicates a binding position to —C (Q ¹ ) (Q ² ) —, and ** indicates a binding position to —O—CO—OL ² —Y. The salt of claim 1, wherein L ² is a single bond or a methylene group. The salt according to claim 1 or 2, wherein Z ⁺ is an arylsulfonium cation. An acid generator comprising the salt according to claim 1. A photoresist composition comprising an acid generator according to claim 9 and a resin having an acid-labile group, which is insoluble or poorly soluble in aqueous alkali solution but soluble in aqueous alkali solution by the action of acid. The photoresist composition of claim 10, further comprising a basic compound. (1) applying the photoresist composition according to claim 10 on a substrate,
(2) drying to form a photoresist film,
(3) exposing the photoresist film to radiation,
(4) baking the exposed photoresist film, and
(5) developing the baked photoresist film with an alkaline developer to form a photoresist pattern
Comprising a photoresist pattern. (1) applying the photoresist composition according to claim 11 on a substrate,
(2) drying to form a photoresist film,
(3) exposing the photoresist film to radiation,
(4) baking the exposed photoresist film, and
(5) developing the baked photoresist film with an alkaline developer to form a photoresist pattern
Comprising a photoresist pattern.